Method checkable_addrs

crates/ixon/src/env.rs:272–279

Addresses of the named constants the kernel typechecker would iterate via `check_const` — every entry in `env.named` minus the `Muts` mutual-block pointers (which aren't standalone checkables). Matches `crates/ffi/src/kernel.rs::all_checkable_ixon_names` but returns addresses rather than names and skips the sort.

(&self)

  /// Reducibility hints, keyed by the constant's projection/standalone
  /// address (i.e. `Named.addr` — the address the kernel sees, **not**
  /// the name-hash address). This is the ANON channel: serialized as §3
  /// (before the name/metadata sections) precisely so anon readers get
  /// hints without touching metadata. Because alpha-equivalent
  /// definitions share one constant address, alias collisions resolve
  /// through [`Env::register_hint`]'s order-independent min-merge — the
  /// map holds one advisory winner per address, NOT the exact
  /// per-definition value (that lives in [`Self::name_hints`]).
  ///
  /// Ingress passes these hints through to `ingress_defn` so the
  /// kernel's lazy-delta tiebreak (`def_eq::def_rank_id`) sees
  /// realistic heights instead of the constant `Regular(0)` fallback.